Art of grinding interchangeable ground-glass bottle-necks and stoppers therefor.



. 0. M. OONRADSON. ART OF GRINDING INTERGHANGEABLE GROUND GLASS BOTTLENEOKS AND STOPPERS THEREFOR.

' APPLICATION FILED JULY 25, 19.07.

911,809; I Patented Feb.9,1909.

2 SHEETS-SHEET 1.

G. M. GONRADSON.

ART or GRINDING INTERGHANGEABLE GROUND GLASS BOTTLE NEGKS AND YSTOPPERSTHEREFOR. 1

APPLICATION FILED JULY 25, 1907.

911,809. l Patented Feb. 9,1909.

2 SHEETS-SHEET 2.

.wlmssszs: P -|NVENTORI mgfawug Cir UNITED srnirns PATENT OFFICE.

CONRAD M. GONRADSON, Ola MADISON, \YIBOONSlN, ASSIGNOR, BY MESNEASSIGNMENTS,

TO PRECISION GLASS GRINDING MACHINE A CORPORATION OF SOUTHDAKOTA.

COMPANY, OF SIOUX FALLS, SOUTH DAKOTA,

ART OF GRINDING INTER-CHANGE ABLE GROUND-GLASS BOTTLE-N E CKS ANDSTOPPERS THEREFOR.

atented Feb. 9, 1909.

Application filed July 25, 1907. Serial No. 385,475.

To all whom it may concern: I

Be it known that I, CONRAD M. CONRAD- SON, a citizen of the UnitedStates, residing at Madison, in the county of Dane-and State ofWisconsm, have invented a new and useful Improvement-in theArt'ofGrinding Inter-- changeable Ground-Glass Bottle-Necks and StoppersTherefor, of which the following is as eoification.

his invention relates to ground glass bottle necks and ground glassstoppers therefor, and its object is to produce 1nterchangeable groundglass bottle-necks and ground glass stoppers therefor, and to obviatethe cumbersome and unduly expensive successive operations of the oldart, the

result of which was, and is,th e production of ground glass jointedbottle necks and stoppers, of "which no stopper pro erlyfits any bottleother than the par-" ticular bottle with which it was originally mated,andof which no bottle properly fits any other stopper than theparticular one with which it was originally mated.

Theground-glass pint-formingart, as it relates to bottlesand stoppers,has long been, andv is, substantially as follows :The trun cated,cone-sha ed interior surface of the glass bottle-nee and the truncated,coneshaped exterior surface of the glass stopper, whether blown orformed in molds, are ini-' tially untrue with reference to thegeometrical axis of the truncated cone; that is, to the ion thwise axesof the bottles and 'ilhe said surfaces are also more or ess, rough,"that is, of a more or less irregu- 'lar, hill-.and-dale condition-IThe first oper-.

ation in the prior art is to gi'ye' approximately'proper form to thesaid surfaces. In the case of the bottle-neck, aso-callied lapping toolrotatably. mounted ,in- 1a mac ehas been used. ;This tool is cone-zshaped, and generally consists of a wooden core spirally-wrappe Withsheet iron. ,The Workman with one hand holds the bottle on the freeend'of the rotating lap, moving the bottleneekbaak and forth on the lalfo 1' "tudinally, while withthe otherhan he ,tejrior an abrasive.mixture. This initial. manual "lapp1ng operation is usually eariiedonuntil the desirede antity of. bot.-- tleenecks has been 'lapped., Thestoppers betweenfthe la and bottle-neck,

are primarily put in a rotating chuck and roughed out by means of a lap,generally seriatim, and holding abottle, in one hand,

with the other hand feeds abrasive mixture between the op osedsurfacesof the stopper and bottleneck, back and forth over the stopper until thejoint-forming surfaces of the bottle are mated;

On the best grade of-work it is frequently the custom to put eachstopper in its bottle, after the lapping operations and oscillate themin relation one to'another by hand to perfect the tightness of joint. 1nthis old art, said surfaces are in fact used. as tools for their ownproduction, one surface modifying the other in such wise that there isno reasonable likelihood of interchangeable mateability. Consequently,tliefurther practice is to tie each stopper to its own bottle, so as tokeep them together for storage and transportatio'n, and for cleaningbefore shipment.

11. paper etween each bottle-neck and its stopper, so as to preventbreakage. The jobbers and retailers also have to keep such bottles andstoppers in mated pairs, as received. By the old process, as a generalrule, the said surfaces are neither properly -round nor straight; andare therefore exceedingly apt to stick together; and the joints are nottight tothe proof alcohol test except by careful manual grinding. ofeach stopper -'-in its own bottle. The practical resultant condition ofthe ground-glass joint art as it relates to bottles and stoppers is thatthe field of use thereof is comparatively restricted, such bottlesandstoppers being unduly expensive and frequentlyv unsatisfactory. is,a'fact, moreover, that no one of said surfaces is uniformly finished,each surface being irregular at the best.

The "advantages of the present invention are, elimination of the expenseof time and labor of the old manual lapping operation;

moving the bottle-neck" ship ing, it is also usual to insert a bit (ifand the production of interchangeable bottlenecks and stoppers, whichmay be shipped separately and used indiscriminately, size for size.

I have discovered that ground glass bottlenecks and ground glassstoppers can be made separatery, and in such wise that ground. 1

glass stoppers of any given size wiii properly fit and form a tightjoint with ground glass bottle-necks of corresponding size, and viceversa; making a non-interiocking, groun glass joint that is generanytight to the proof acohol test.

My new method involves the use of glassgrinding tool in effecting aseries of changes or transformations of the joint forming surfaces, andby my new method I can grind quantities of grass bottles or stoppersindependently one of another, yet soaccurately that the stoppers will beinterchangealxe with the bottles, and vice versa, and aiways a perfectfit, as stated. My new method is not only more precise, but is very muchmore rapid than the old method of grinding the joint-forming surfaces. I

In the drawings, illustrating the principle of my invention and the bestmode now pencil C the maximum distance the grinding pen- '65 known to me,of appying that principle, Figure l is a vertical section of a glassbottle with a stopper in place, the joint-forming surfaces being formedin accordance with my invention. Fig. 2 is a partial sectional elevationof a bottle with a glass-grinding implement, shown in two positions, thefirst position showing a grinding implement about to enter thebottle-neck and the second position showing the inner end portion of thegrinding implement below the ground, joint-forming surface. Fig. 3 is aplan development of a ground glass-surface enlarged; and Fig. 4 is aplan development of the surface shown in ig. 3 after being groundspirally and reversely. j

Referring to the drawings,in Fig. l, A represents a glass bottle, and Ba glass stopper; 1 is the inside ground or joint-forming surface of thebottle-neck, and 2is the inside surface of the bottle-neck below theground portion 1. As a matter of convenience, the ground surface 1terminates abruptly at 3 with the unground portion 2-.

In Fig. 1 5 is the usual neck of the bottlestopper B. between the headof the stopper and the ground joint forming surface 6 thereof.-

- In carrying out my method, I preferably rovide a grinding implement ofany proper orm or contour, which may be in the form of a grinding pencilC, as shown. Such a pencil is shown in Fig. 2, in two positions; Cindicatin the maximum distance the grindin C extends inside thebottle-neck, an

oil is withdrawn from the bottle inthe operal. his will depend on thebreadth of the glass surface to be ground. 'lhc grinding pencil rotates,during its operation, in contact wit h the glass surface operated on, ata high rule of speed, and has inol'crably a rmriprocating, cndwisemotion relative to the bottle and parallel with the side of the insideground surface or stopper-seat 1, which may be couical, as shown, or ofany other desired shape.

It is immaterial whether, during the grinding operation, the grindingimplement rcciprocates longitudinally or is rotated without suchlongitudinal movoinci'it, provided, in the latter case, the bottle orstopper is given lengthwise movement. If desired, both the bottle andthe grinding implement may reciprocate during the rotation of thegrinding implement, at which time the bottle prefer ably rotates at acon'iparatively low rate of speed, and preferably in the oppositedirection to that in which the pencil rotates. 'lhc longitudinalmovements of the bottle-neck or grinding implement in relation to oneanother are had with the operating surface of the grinding implement incontact with the glass surface to be ground. 'I he ground glass. surfaceof the stopper B, shown in Fig.

1, is ground in the same way as the inner sur face 1 of the bottle-neck,the grinding'implcment rotating in contact with the exteriorjoint-forming surface of the stopppr, and the stopper and implement,either or oth having longitudinal movement at such time.

'i he abrasive or cutting surface of the grinding i'm )lement, duringits movement in relation to t 1e lass surface to be ground (or thelongitudinal movement of said surface in relation, approximately, to thelengthwise axis of the grinding implement,) initially causes anapproximately spiral furrowing a:

of the surface. The reverse endwise movement of either the grindinimplement or bottle, one in relation to the other, or of both inrelation to one another, generates on the initially spirally groundsurface, a re verse spiral furrowing v, and the successive longitudinalmovements referred to result in the cutting of a spirally furrowedsurface on an underlying spirally roughened surface, so that when thegrinding is done, the ground, joint-forming surface is broken up intominutebut approximately uniformly s aced elevations and depressions, andwith tlie result that all ground bottle-necks of a given size will fitthe corresponding sizes of independently ground bottle-stoppers, andvice .versa. '1 here may be as many-series of spiral furrowings orcuttings as are desired to .produce the required finish of thejointforming surfaces. Each grinding operation begins at one edge orside of the surface to be ground, and is-continued to the other ed eor-side of such surface.

11 working the old rocess, the floating abrasive particles in t e.abrasive mixture wandered more or less at random, and conseuently werenot definitely controlled, so t at the result was a total lack ofuniformity in the j oint-forming surfaces of bottlenecksand ground glassstoppers therefor, consisting ingrindingjthe-contacting, joint-formingsurfaces thereof uniformly and spirally Q edgetoedge..-

.2. The improvement in'the art of interchangea 1e, ground glass bott enecks and ground glass stoppers therefor, consist-2o ing in initiallygrinding the contacting-jointforming surfaces thereof uniformly andspirally from edge to edge; and in then grinding the initiallygroundsurface from edge to v edge, .reversely, uniformly and spirally;

C RA MJCONRADSON.

Witnesses:

FRANK L. HOWARD," Y HENRY R. KENNEDY; v

